Support for charged particle accelerator magnet sections



Jan. 23, 1968 W. W. SALSIG, JR 3,364,636

SUPPORT FOR CHARGED PARTICLE ACCELERATOR MAGNET SECTIONS 2 Sheets-Sheet 1 Filed June 10, 1966 ATTORNEY.

W. W. SALSIG, JR

2 Sheets-Sheet 2 R O N E V m WILLIAM W. SALSIG, JR.

ATTORNEY.

Jan. 23, 1968 FOR CHARGED PARTICLE ACCELERATOR MAGNET SECTION UPPCET Filed June 10, 1966 United States Patent C) 3,364,636 SUPPGRT FOR CHARGED PARTICLE ACCELERATQR MAGNET SECTIONS Wiliiam W. Salsig, In, Kensington, Calif., assignor to the United States of America as represented by the United States Atomic Energy Commission Filed lune I0, 1966, Ser. No. 556,785 9 Claims. (Cl. 52-169) The present invention relates to structure for the support of heavy fixed loads and more particularly to adjustable supports for the beam guiding magnets of a large charged particle accelerator, The invention described herein was made in the course of, or under, Contract W7405- eng-48 with the United States Atomic Energy Commission.

In a high energy particle accelerator of the type having a series of beam guiding magnet sections forming a substantially circular beam path it is necessary to adjust and maintain the position of the magnet sections, each typically weighing about forty tons, to a very close tolerance. For instance the requirements for aligning magnet sections with respect to the theoretical particle orbit centerline may be as close as 0.01 inch in a vertical direction and 0.02 inch in a horizontal direction. It is necessary to be able to maintain the magnet alignment to Within these tolerances in spite of soil settling or other factors such as movement resulting from earthquakes.

In the past, various combinations of hydraulic and mechanical jacks have been used to support the magnets of accelerators. Tie rods and other similar means have been used to brace the structure laterally. As an accelerator approximately a mile in diameter, comprising several hundred magnet sections, is now being designed, such previously used methods may not be satisfactory and a very difficult problem exists in providing stable adjustable supports for an accelerator of such relatively great size.

The present invention is designed particularly for an accelerator which is to be situated on a site characterized by compressible sofls. In the case of an area having a thick layer of compressible soil, vertical settling of the surface soil, which may vary at different portions of the accelerator, is a particular problem. Accordingly, the present invention provides for separating the vertical support from the horizontal restraints so that the former may be derived from a relatively stable area deep in the ground.

In particular, in a series of successive magnet sections, two such sections for example, rest on a steel beam which extends in a generally circumferential direction along the particle orbit. The adjacent ends of each two successive beams are supported on a cross beam which in turn rests on two support assemblies, one at each end of the crossbeam. In each such assembly the vertical load imparted by the cross-beam will be carried on a long pile which extends downwardly and freely through a vertical shaft in the surface layers of the soil, the lower end of the pile being supported in deep or very well settled ground. This eaves the upper end of the pile free to yield horizontally to some extent. A flexible hinged linkage secured to the floor adjacent to the upper end of the pile secures the cross-beam and its supported beams against horizon al motion with respect to the floor but permits vertical motion. This permits settling of the surface soil and the fioor which it supports Wi hout effecting the vertical position of the accelerator magnets. Of course any horizontal movement of the floor at a particular location will require horizontal adjustment of the cross beam to bring it back to the original position and thus maintain the desired maget alignment. However, horizontal soil movements at the surface are usually quite small compared to vertical movements. Horizontal positioning of each magnet may be accomplished on the support beam within rather narrow limits.

Accordingly it is an object of the present invention to provide adjustable support means for the magnets of a charged particle accelerator with which the effects of unstable surface soil can be minimized.

It is a further object of this invention to provide a more convenient and reliable means for maintaining magnet positioning to very close tolerances in a large particle accelerator.

It is another object of the present invention to provide support for the magnets of a particle accelerator, in a vertical direction, which is independent of the anchorage in the horizontal direction.

It is a still further object of this invention to provide vertical support for the magnets of a particle accelerator from deep and well settled soils.

The invention together with further objects and advantages thereof will be best understood by reference to the following specification in conjunction with the accompanying drawing of which:

FIGURE 1 is an elevation view partly in cross-section of a support assembly for a section of a charged particle accelerator.

FIGURE 2 is a perspective view, partly cut away, further showing the supporting structure for the accelerator,

FIGURE 3 is a plan view of the structure shown in FIGURES 1 and 2 showing the means of lateral adjustment,

FIGURE 4 is a detail drawing of a remote lateral adjustment mechanism for the support structure,

FIGURE 5 is a section view taken along line 5-5 of FIGURE 4,

FIGURE 6 is a detailed view of an alternate manual lateral adjustment mechanism, and

FIGURE 7 is an end view of the mechanism of FIG- URE 6.

Referring now to the drawing and particularly to FIG- URES 1 and 2, the end of a main support beam 11 for the accelerator beam directing magnets 10* is shown resting on two pedestals 12 which are secured on the top surface of a cross-beam 13. The cross-beam 13 also has two other pedestals 14 at the top surface for the purpose of supporting the adjacent end of the next main support beam 16. The second main beam 16 is ofi-set laterally from the first beam 11 because the two magnets 19 supporied by the beam 11, which may be C magnets for example, have openings in one direction with the center of gravity of the magnets on one side of the accelerator ion orbit and the two C-rnagnets mounted on the next beam 16 have openings facing in the other direction and therefore have a center of gravity on the other side of the beam path. An equivalent system may be utilized should H magnets be employed.

Referring particularly to FIGURE 1, two different embodiments of the support structure are shown at opposite ends of the cross-beam 13, that at the right end being adapted for remote control of adjustments, for example where radiation levels preclude access, and that at the left end being a simpler manually adjustable variation. Considering now the remotely controllable embodiment, a hollow cylindrical element 17 penetrates each end of the cross-beam 13 and is welded thereto, the axis of the cylinder elements being vertical. A post 18 disposed against the bottom of the right cylinder 17 has a lower end resting on the top fiat surface of a cylindrical bellows 19 which is internally pressurized in this instance through a pipe 20 connected to a source of hydraulic fluid under pressure for controllably raising the load. Alternately, the enclosed region surrounding bellows 19 could be pressurized to effect the lifting. The bottom surface of the bellows 19 is seated in a cylindrical structure 21 the top rim of which extends above the top of the bellows. The cylinder 21 fits within the top of a tubular pile 22 and is secured therein 'by means of an annular element 23 which is welded to the top edges of both cylinder and pile. The pile 22 exends downward inside a sleeve which does not reach the bottom of the pile. The sleeve 25 is of sufficient diameter to permit the upper portions of pile 22 a small amount of horizontal movement in any direction. The pile 22 is driven info the ground at its base or in some instances may be driven all the way to bedrock for greater support. Interior portions of pile 22 which are above the surface of the ground into which the pile is driven may be filled with concrete 49 where such additional stiffening of the pile is desired. The space between the pile 22 and sleeve 25 is preferably filled by some yieldable substance with high viscosity such as bunker oil which will resist sudden movements but will yield to a steady continued force. Also carried on top of pile 22 and secured to the element 23 is a flat plate 24 having a central opening to permit the unobstructed passage of the post 18 therethrough. The post 18 is threaded and a nut 25 thereon rests on the top of plate 24 to support the weight of one end of the beam 13, the other end being similarly supported. The nut 26 may be turned by Worm 27, as is well known in the art of mechanisms, thus providing means for remotely controlled adjustment at locations where radiation is high. To adjust the vertical position of the beam 13 upward the bellows 19 is filled with fluid under pressure by means of the tube 26 sufficient fiuid being supplied to move the beam upward slightly more than the required adjustment. The nut 26 is then screwed down to the proper position and fluid is then removed from bellows 19 to lower the post 18 and transfer the load from the bellows to the nut 26. To lower the end of the beam 13 the bellows 19 is filled with fluid until the load is removed from nut 26. The nut 26 is then screwed upward on post 18 to the desired point whereupon fluid is removed from bellows 19 to transfer the load back to the nut with the end of the beam at the desired elevation.

At locations where radiation is low enough to permit making manual adjustmens of the elevation of the ends of beam 13 a basically similar but simpler support is used to carry the vertical load. This condition will prevail at the majority of locations. In this arrangement, shown at the left end of cross-beam 13 in FIGURE 1, a top plate 24' is secured to the top edges of pile 22. A post 18 supported on plate 24 carries the weight of the beam 13 by means of the cylindrical element 17. The post 18' has an axial bore through which a rod 28 passes and is screwed into a central threaded bore in plate 24'. Post 18 has a shim stack 29 making up part of the leng'h thereof, the shim stack providing the means for adjusting the vertical position of the beam 13. To make this adjustment it is necessary to employ a separate jack to take the load from the post 18 The lid is removed from the cylindrical element 17, the rod 28 is unscrewed from the plate 24' and withdrawn and shims may then be removed or added to shim stack 29 as required. By a reverse process the load is then returned to the post 18.

This vertical support of the ends of cross-beam 13 on the upper end of a long pile 22 or 22' provides practically no horizontal anchorage since the piles are of sufiicient length that a relatively small force in a horizontal direction can produce an inch or two of deflection. To anchor the cross-beam 13 against such movement, a hinged bellows like structure 31 is disposed at the top of pile 22 and is secured to the bottom of the cross-beam and at the top of sleeve 25 which is anchored in the cement flooring 39. Hinge structure 31 comprises two long rectangular pla es 32 and 33 placed with plate 32 above plate 33 with a portion of the length of plate 32 near each end bent downwards and a similar portion of plate 33 near each end bent upwards. The touching tips at each end of place 32 and 33 are welded together. A bore in the fiat central portion of plate 32 fits around the lower portion of cylindrical element 17 with the long dimension of the plates parallel to cross-beam 13.

Plae 33 rests on the flat end surface of a tubular element 34 to which it is welded and the ends protrude therebeyond. The lower end of tubular element 34 which surrounds the upper end of pile 22 rests on flat annular base plates 36 which rest on the floor 33. The tubular element 34 and plates 36 are secured to the floor 3G by means of embedded hole 37. The outer end of the hinge structure 31 is further braced and stitfened 'by the use of two additional rectangular plates 38 and 39. The first plate 33 is secured at its upper end to the outer joined ends of plates 32 and 33 and extends downwardly. The second plate 39 is secured to the lower end of plate 32} and extends inwardly in a direction parallel to the bent end portion of plate 33 at its outer end to meet the element 34 to which its end is shaped to fit and to which it is secured by welding. The length of the plate 39 is the same as the length of the bent end portion of plate 33. An identical structure at the inner ends of plates 32 and 33 is composed of plates 41 and 42 secured in a manner similar to that used for plates 38 and 39. Hinge structure 31 thus provides great stiffness in the horizontal plane, in a direction transverse to the cross-beam 13, but is relatively free to move vertically so that the vertical load on the crossbeam may be carried, and the vertical position thereof determined, by pile 22 and the post 18. An identical hinge structure 31 is provided at each end of crOLS-beam 13 to prevent transverse movement of the cross-beam in the horizontal plane.

To provide anchorage for cross-beam 13 in the horizontal plane in a direction parallel to the cross-beam a hinge structure 31 similar to hinge structure 31 may be disposed at right angles to the latter at one end of the cross-beam as shown in FIGURE 2 thus securing the beam from movement in any direction in the horizontal plane. However in the hinged structure 31 the plates 32 and 33' are not welded together but are provided with adjustment means 44 for remote adjustment of the lateral positioning of the plates and thus the axial positioning of the cross-beam 13. Referring now to FIGURES 3, 4, 5, 6 and 7 the adjustment means 44, one of which is provided at each end of the pair of plates 32' and 33, has two split nuts 45 details of which are shown in FIG- URE 5, which clamp tightly on the central portion of a lead screw 46 under the action of a spring washer 47 acting through a pull rod 48. This eliminates a few thousandths of an inch backlash, and also prevents turning of the lead screw 46 except when an adjustment is required in which event the application of fluid pressure to hydraulic bellows 49 through tube 51 compresses the spring 47 and releases the pressure on the split nuts 45. The two split nut devices 45 are attached to the top plate 32'. Two additional split nut devices 52, similar to the devices 45, are attached to the bottom plate 33, as shown in FIGURE 3, and are threaded to the two end portions of lead screw 46. The central portion of lead screw 46 has a screw pitch which differs from the screw pitch at the two end portions so that the movement between the two nuts 45 attached to the top plate 32' as compared to the two nuts 52 attached to the bottom plate 33' is a difierential movement depending on the diiference in the thread pitch when the lead screw 46 is turned by means of an hydraulic gear motor 53 also remotely controlled.

When the longitudinal adjustment of the position of cross-beam 13 may be made manually, the remote adjustment units 44 are replaced with a simpler and less costly adjustment means 55, shown in FIGURES 6 and 7. This adjustment means 55 comprises a bar 53 welded to upper plate 32' and a second bar 54 welded to lower plate 33' is normally in a position approximately below the bar 53. A third bar 56 bolted to the bar 54 with a spacer 57 therebetween is thus also spaced from the bar 53. The bar 53 is also bolted to bar 56 with a shim stack 58 therebetween thus securing the plates 32' and 33' in the desired position to properly locate cross-beam 13 in its longitudinal direction. Medial of the width of plates 32' and 33' is a bar 59 attached to the upper plate 32' and a second bar 61 attached to lower plate 33' and spaced apart from the bar 59. Both bars 59 and 61 are penetrated by a threaded bolt 62 the axis of which is parallel to the edges of plates 32 and 33'. Nuts for the bolts 62 are provided on each side of both bars 59 and 61. The edges of plates 32' and 33' are bolted together by bolts 63 except when an adiustrnent is required. When such adjustment is required the bolts 63 holding the edges of plates 32' and 33' are loosened and the bolt holding the shim stack 58 is then loosened and the shim stack removed. By means of the nuts on bolt a2 the plates 32' and 33 are moved until the shim stack 58 of the desired thickness may be placed between the bars 53 and 56 which are then bolted together again. The bolts 63 are then retightened to better secure the position of the cross-beam 13.

It will be evident to those skilled in the art that many variations are possible Within the spirit and scope of the invention. Therefore it is not intended to limit the invention except as defined by the tohowing claims.

What is claimed is:

1. In a support srtucture for a heavy load disposed over a thick soil layer, wherein a vertical passage extends downwardly into said soil layer, the combination comprising a long vertical pile disposed under said load and extending downwardly Within said passage, said pile being of less diameter than said passage whereby the upper portion of said pile is free of vertical restraint by the upper portion of said soil layer, means securing the lower end of said pile at the base of said passage, and a vertically yieldable horizontally rigid linkage connecting said load to said upper portion of said soil layer.

2. A support structure as described in claim 1 and comprising the further combination of a vertically adjustaole element disposed between said load and the upper end of said pile for selectively varying the vertical position of said load.

3. A support structure as described in claim 1 wherein said vertically yieldable horizontally rigid linkage is comprised of a first member having a first end anchored to said upper portion of said soil layer and a second member having a first end coupled to said load, said first and second members being disposed at an acute angle with respect to each other and being joined together at the second ends.

A support structure as described in claim 1 wherein said vertically yieldable horizontally rigid linkage is comprised of a first member having a first end anchored to said upper portion of said soil layer, a second member having a first end coupled to said load, said first and second members being disposed at an acute angle with respect to each other and being joined together at the second ends, a third member disposed below said first member in substantially parallel relationship thereto and having a first end also anchored to said upper portion of 6 said soil layer, and a fourth member extending vertically between the second end of said third member and the joined ends of said first and second members.

5. A support structure as described in claim 1 wherein said vertically yield able horizontally rigid linkage is comprised of a pair of flat first members disposed on opposite sides of said pile each having a first end anchored to said upper portion of said soil layer and a pair of flat second members similarly disposed on opposite sides of said pile each having a first end coupled to said load, the first and second members on each side of said pile being disposed at an acute angle with respect to each other with the second ends thereof being secured together.

6. A support structure as defined in claim 5 further comprised of a pair of third fiat members each being disposed below one of said first members in substantially parallel relationship thereto and each having a first end also anchored to said upper portion of said soil layer, and a pair of fourth fiat members each extending from the second end of one of said third members to the joined second ends of said first and second members thereabove.

7. in a support for a charged particle accelerator magnet section having a support beam thereunder and wherein a vertical passage extends downwardly into the ground beneath each end of said beam, the combination comprising a first and a second vertical column disposed under opposite ends of said beam each extending downwardly within said passage thereunder, said columns being of less diameter than said passages whereby the upper portions of said columns are free of vertical restraint by the upper portion of said ground, means securing the bases of said columns within said passages, and a vertically yieldable horizontally rigid link coupling said beam to said upper portion of said ground at the top of each or" said columns, each of said links having a first member with a first end anchored to said upper portion of said ground and a second member having a first end coupled to said beam, said first and second members being disposed at an acute angle with respect to each other with the second ends thereof being joined together.

8. A support for a charged particle accelerator magnet section as defined in claim 7 wherein a pair of said links is disposed at each of said columns on opposite sides thereof.

9. A support for a charged particle accelerator magnet section as defined in claim 8 wherein an additional pair of said links is disposed at at least one of said columns at right angles to the first pair of said links thereat.

References Iited UNITED STATES PATENTS 1,793,525 2/1931 Stafford 52'l22 2,550,987 5/1951 Flores 52-126 X 2,625,815 1/1953 Black 52122 3,232,015 2/1966 Latham 52294 X FOREIGN PATENTS 470,652 1/ 1951 Canada.

FRANK L. ABBOTT, Primary Examiner.

ALFRED C. PERI-TAM, Examiner. 

1. IN A SUPPORT STRUCTURE FOR A HEAVY LOAD DISPOSED OVER A THICK SOIL LAYER, WHEREIN A VERTICAL PASSAGE EXTENDS DOWNWARDLY INTO SAID SOIL LAYER, THE COMBINATION COMPRISING A LONG VERTICAL PILE DISPOSED UNDER SAID LOAD AND EXTENDING DOWNWARDLY WITHIN SAID PASSAGE, SAID PILE BEING OF LESS DIAMETER THAN SAID PASSAGE WHEREBY THE UPPER PORTION OF SAID PILE IS FREE OF VERTICAL RESTRAINT BY THE UPPER PORTION OF SAID SOIL LAYER, MEANS SECURING THE LOWER 